How can Ireland secure their fourth Six Nations title with a round to spare this weekend?
Joe Schmidt's side boast a five-point lead over England in the standings ahead of the visit of Scotland to Dublin.
Ever since the fixture list for the 2018 edition of the Six Nations was first announced back in January, many seemed to take for granted that a second successive final day showdown between England and Ireland - this time at Twickenham - would stand as a potentially mouth-watering Grand Slam decider.
That was, of course, until round three, when Glasgow Warriors centre Huw Jones inspired Gregor Townsend's Scotland to a first home Calcutta Cup win for 14 years to inflict only the second loss of Eddie Jones' reign, end any hopes of a Grand Slam or Triple Crown and deal a potentially significant blow to underpar England's chances of winning a record third successive title.
In stark contrast, hours earlier in Dublin, three-time champions Ireland maintained their formidable recent record at the Aviva Stadium with a thrilling 37-27 defeat of Wales that has led to more excited talk of only a third-ever clean sweep and a first since 2009.
Such an impressive victory has put Joe Schmidt's side in pole position to end their three-year barren run, something that could well happen as soon as this weekend and with a round to spare depending on the outcome of their home meeting with Scotland - who still have a slim chance of success themselves after those memorable Murrayfield heroics - and England's subsequent 'Le Crunch' clash with France in Paris.
Quite simply, if Ireland, who now boast a five-point lead in the standings, were to rack up four tries and a bonus-point victory against opponents that are without a win on the the Emerald Isle since 2010 and have triumphed in only six of their last 46 Six Nations away fixtures, then England would need to do the same in order to make that eagerly-anticipated St Patrick's Day encounter more than merely a reversal of last year's script and a chance to stop their rivals from claiming a coveted Grand Slam on hostile territory.
Team news
Schmidt has restored the fit-again tighthead prop Tadhg Furlong to his front row against Scotland at the expense of Andrew Porter, while Leinster teammate Garry Ringrose will make his first appearance of the tournament after recovering from ankle surgery.
Munster centre Chris Farrell - man of the match against Wales - has joined the likes of Robbie Henshaw and Jared Payne on the sidelines after being ruled out for the remainder of the season with an anterior cruciate ligament injury suffered in training last week.
The Kiwi coach has also handed a vote of confidence to locks Devin Toner and James Ryan, whose second-row partnership remains intact despite the return to fitness of Ulster's Iain Henderson, who settles for a replacement berth.
Scotland's only change from that 25-13 win over England in which the visitors were denied even a losing bonus point sees young Edinburgh full-back Blair Kinghorn handed his maiden Test start on the right wing due to a back problem suffered by Tommy Seymour. Glasgow's Lee Jones is promoted to the bench, meanwhile.